• Title/Summary/Keyword: length variation

Search Result 2,251, Processing Time 0.032 seconds

Genetic Variation of a Single Pollen-derived Doubled Haploid Population in Rice

  • Moon, Huhn-Pal;Kang, Kyung-Ho;Ahn, Sang-Nag;Choi, Seon-Hee
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.43 no.4
    • /
    • pp.250-253
    • /
    • 1998
  • Somaclonal variation was observed in the field on doubled haploid plants derived from single pollen of a rice cultivar "Hwaseongbyeo". The variations of seven quantitative traits including plant height and one qualitative trait (pubescence) in 436 lines ($R_2$ generation) were analyzed. The number of lines which fell beyond the boundaries of the 95% confidence intervals of the check variety, Hwaseongbyeo was checked for each quantitative trait, and of those fertility showed the highest variation frequency (85.6%), followed by plant height (77.5%), flag leaf length (66.5%), grains per panicle (42.2%), days to heading (34.5%), panicle length (30.7%) and panicles per hill (22.7%). And the variations of quantitative traits except days to flowering appeared to move in the negative direction compared to "Hwaseongbyeo". Variability within lines was also observed for quantitative and qualitative traits. Twenty-nine $R_2$ lines (7%) segregated for pubescence and 130 $R_2$ lines (30%) showed variation with regard to fertility. This suggests that mutations usually occur before diploidization. Twenty-nine $R_2$ lines representing a wide spectrum of variation were chosen for RAPD analysis. The number of lines showing DNA polymorphism compared to Hwaseongbyeo ranged 0 from to 10 according to the primer used and this seems to indicate that specific loci have highly mutable genomic site.utable genomic site.

  • PDF

Mitochondrial DNA polymorphism in Fourteen Geographical Strains of Drosophila melanogoater (세계 14지역 계통에 대한 초파리 미토콘드리아 DNA의 다형현상)

  • 김봉기
    • The Korean Journal of Zoology
    • /
    • v.31 no.3
    • /
    • pp.218-224
    • /
    • 1988
  • Restriction endonucleases were used to search for intraspecific variation at 32 cleavage sites in mitochondrial DNA(mtDNA) purified from fourteen strains of Drosophila melanogaster helonging to different localities of the world. mtDNA of D. melanogaster was displayed site variation(Hpall, Haelll and Seal endonucleases) and length variation(maxirnum 550bp). Six genotypes, Ml, M2, M3, M4, M6 and M7, could be distinguished based on ihe site types witti a low average of intraspecific substitution rate (1.88%),but M5 type of Ogasawara strain in Japan was not detected in this study. A possible explanation for the low divergence was that mtDNA variation of fourteen strains in D. melanogaster could not he accumulated sufficiently owing to recent divergence of few individuals, and that sequence divergence was prevented by frequent migration in spite of the geographical isolation.

  • PDF

A study on the shoulder composition methods of power shoulder jackets and corresponding details (파워숄더 재킷의 어깨 구성 방법과 디테일 대응 분석)

  • Park, Jeongah;Lee, Jeongran
    • The Research Journal of the Costume Culture
    • /
    • v.29 no.3
    • /
    • pp.388-405
    • /
    • 2021
  • This study classifies the compositional methods of power shoulder jackets from 1980 to the present. It analyzes the relevance of jacket details according to how the power shoulder changes and its compositional methods by era. The research subdivides shoulder compositional techniques into seven, based on shoulder variation, sleeve variation, and the body and sleeve combination. The researcher investigates the frequency and trends of composing shoulders and analyzes details pertaining to the silhouette, jacket length, collar shape, and front closure. The most common method of shoulder composition is an angular shoulder variation. The others are a rounded shoulder variation, puffed sleeve, sleeve variation using pattern incision, raglan and kimono sleeves, and a shoulder variation that expanded the angle and width. The frequency differs slightly for each era. The relationship between shoulder compositional methods and details of power shoulder jackets is statistically significant, showing period-related differences. The homogeneity analysis results reveal that the shoulder composition of power shoulder jackets, the times, and details fall into distinct groups. This analysis shows that the silhouette, length, collar, and front closure of the power shoulder jacket differ depending on the power shoulder's compositional methods. Moreover, the shape of the power shoulder jacket is distinctly different. One can use this data to help develop the power shoulder jacket design by reflecting the details of shoulder compositional methods and changing trends over time.

Variations in hospital length of stay for diagnosis-related groups among health care institutions (DRG 지불제도 참여기관의 재원일수 변이에 관한 연구)

  • Lee Kee-Sung;Kang Hee-Chung;Nam Chung-Mo;Cho Woo-Hyun;Kang Hye-Young
    • Health Policy and Management
    • /
    • v.16 no.2
    • /
    • pp.77-95
    • /
    • 2006
  • The present study was conducted to examine the degree of variation in length-of-stay (LOS) among health care institutions participating in 17 diagnosis-related groups (DRGs) payment system and to find out hospital characteristics affecting the variation. Electronic medical claims data for treatments of severity classification '0' of 17 DRGs provided for two $years(2003{\sim}2004)$ were collected. For each DRG, the degree of variation in average LOS among health care institutions were analyzed using the random effect model. For DRGs showing significant differences in LOS, multiple regression analyses were performed to find out factors associated with LOS. Significant variations in LOS were observed 9 DRGs including unilateral/bilateral lens procedures, adult/child tonsilectomy, other anal procedures, bilateral adult/child herniorraphy, unilateral child herniorraphy, and hysterectomy, and hysterectomy using laparoscopic procedure. Among the 9 DRGs, five DRGs were selected to investigate the factors explaining for the variation. It was observed that the location of institution was significant predictors for all five DRGs. Within the same DRGs, LOS was significantly shorter among the institutions located in Seoul than those in other areas. As compared to clinics, hospitals and general hospitals/tertiary care institutions showed significantly longer LOS for DRGs of lens procedures, tonsilectomy, and other anal procedures. It is recommended that the institutions located in other than Seoul area benchmark the strategies of the institution in Seoul in efficiently managing LOS. Also, significant variation within the same severity classification such as other anal procedures implies the imminent need for improvement of patient classification system.

Parameter Estimation for Range Finding Algorithm of Equidistance Stereo Catadioptric Mirrors (등거리 스테레오 전방위 렌즈의 위치 측정 알고리듬을 위한 파라미터 측정에 관한 연구)

  • Choi, Young-Ho;Kang, Min-Goo;Zo, Moon-Shin
    • Journal of Internet Computing and Services
    • /
    • v.8 no.5
    • /
    • pp.117-123
    • /
    • 2007
  • Catadioptric mirrors are widely used in automatic surveillance system. The major drawback of catadioptric mirror is its unequal image resolution. Equidistance catadioptric mirrir can be the solution to this problem. The exact axial alignment and the exact mount of mirror are the sources that can be avoided but the focal length variation is inevitable. In this paper, the effects of focal length variation on the computation of depth and height of object' point are explained and the effective and simple focal length finding algorithm is presented. First two object's points are selected, and the counterparts on the other stereo image are to be found using MSE criterion. Using four pixel distance from the image center, the assumed focal length is calculated. If the obtained focal length is different from the exact focal length, 24mm, the focal length value is modified by the proposed method. The method is very simple and gives the comparable results with the earlier sophisticated method.

  • PDF

Switching Characteristics due to the Impurity Concentration and the Channel Length in Lateral MOS-controlled Thyristor (수평 구조의 MOS-controlled Thyristor에서 채널에서의 길이 및 불순물 농도에 의한 스위칭 특성)

  • Kim, Nam-Soo;Cui, Zhi-Yuan;Lee, Kie-Yong;Ju, Byeong-Kwon;Jeong, Tae-Woong
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.18 no.1
    • /
    • pp.17-23
    • /
    • 2005
  • The switching characteristics of MOS-Controlled Thyristor(MCT) is studied with variation of the channel length and impurity concentration in ON and OFF FET channel. The proposed MCT power device has the lateral structure and P-epitaxial layer in substrate. Two dimensional MEDICI simulator and PSPICE simulator are used to study the latch-up current and forward voltage-drop from the characteristics of I-V and the switching characteristics with variation of channel length and impurity concentration in P and N channel. The channel length and N impurity concentration of the proposed MCT power device show the strong affect on the transient characteristics of current and power. The N channel length affects only on the OFF characteristics of power and anode current, while the N doping concentration in P channel affects on the ON and OFF characteristics.

A Study of Combustion Instability Mode according to the Variation of Combustor Length in Dual Swirl Gas Turbine Model Combustor (연소실 길이에 따른 이중선회 가스터빈 모델 연소기에서 연소불안정 모드 연구)

  • Jang, Munseok;Lee, Keeman
    • Journal of the Korean Society of Combustion
    • /
    • v.21 no.2
    • /
    • pp.29-37
    • /
    • 2016
  • This study described the experimental investigations of combustion instability in a model gas turbine combustor. Strong coupling between pressure oscillations and unsteady heat release excites a self-sustained acoustic wave, which results in a loud and annoyed sound, and may also lead to a structural damage to the combustion system. In this study, in order to examine the combustion instability phenomenon of a dual swirling combustor configuration, the information of heat release and pressure fluctuation period with respect to the variation in both thermal power and combustor length was collected experimentally. As a result, the fundamental acoustic frequency turned out to increase with the increasing thermal power without respect to the combustor length. The frequency response to the combustor length was found to have two distinct regimes. In a higher power regime the frequency significantly decreases with the combustor length, as it is expected from the resonance of gas column. However, in a lower power regime it is almost insensitive to the combustor length. This insensitive response might be a result of the beating phenomenon between the interacting pilot and main flames with different periods.

The Variation of Culm Characteristics of Phyllostachys bambusoides Associated with Altitudinal Gradient in Mt. Jiri (지리산(智異山) 지역(地域)의 해발고(海拔高)에 따른 왕대의 간형질(稈形質) 변이(變異))

  • Jeong, Jong Sung;Lee, Kang Young
    • Journal of Korean Society of Forest Science
    • /
    • v.77 no.2
    • /
    • pp.235-241
    • /
    • 1988
  • This study was carried out to identify the variation of culm characteristics of Phyllostachys bambusoides associated with attitudinal gradient in Mt. Jiri. The results obtained were summarized as follows : It was estimated that the average temperature at the altitude of 400 meters of Mt. Jiri was $12^{\circ}C$ which was closely associated with the horizontal distributions. It was observed that frequency distribution of the culm height, D.E.H. and clear length from the altitude of 200 meters to 400 meters shown at higher than that from 500 meters to 600 meters, and that frequency of clear length/culm height showed about equal for both altitude ranges. In the case of culm height, D.E.H. and clear length/culm height, coefficients of variation ranged from 15 percent to 25 percent, and those of clear length were over 25 percent for both altitude ranges. It was observed that culm height, D.E.H., clear length and clear length/culm height among each altitude ranges were significant at the 1 percent level. The Duncan's Test of culm characteristics among altitude ranges distinguished bamboos of below 400 meters from bamboos of over 500 meters. The correlation coefficients among culm characteristics of Phyllostachys bambusoides associated with attitudinal gradient were shown to be highly significant. In conclusion, the variation of calm characteristics of Phyllostachys bambusoides was large for below 400 meters and these results suggest that planting of the species should be done below 400 meters.

  • PDF

Frequency of Solar Spotless Days and Flare Index as Indices of Solar Cycle Activity

  • Oh, Suyeon
    • Journal of Astronomy and Space Sciences
    • /
    • v.31 no.2
    • /
    • pp.145-148
    • /
    • 2014
  • There was a research on the prolongation of solar cycle 23 by the solar cyclic variation of solar, interplanetary geomagnetic parameters by Oh & Kim (2013). They also suggested that the sunspot number cannot typically explain the variation of total solar irradiance any more. Instead of the sunspot number, a new index is introduced to explain the degree of solar activity. We have analyzed the frequency of sunspot appearance, the length of solar cycle, and the rise time to a solar maximum as the characteristics of solar cycle. Then, we have examined the predictability of solar activity by the characteristics of preceding solar cycle. We have also investigated the hemispheric variation of flare index for the periods that the leading sunspot has the same magnetic polarity. As a result, it was found that there was a good correlation between the length of preceding solar cycle and spotless days. When the length of preceding solar cycle gets longer, the spotless days increase. It is also shown that the shorter rise time to a solar maximum is highly correlated with the increase of sunspots at a solar maximum. Therefore, the appearance frequency of spotless days and the length of solar cycle are more significant than the general sunspot number as an index of declining solar activity. Additionally, the activity of flares leads in the northern hemisphere and is stronger in the hemisphere with leading sunspots in positive polarity than in the hemisphere with leading sunspots in negative polarity. This result suggests that it is necessary to analyze the magnetic polarity's effect on the flares and to interpret the period from the solar maximum to solar maximum as the definition of solar cycle.

Measurement of Variation in Water Equivalent Path Length by Respiratory Organ Movement

  • Minohara, Shinichi;Kanai, Tatsuaki;Endo, Masahiro;Kato, Hirotoshi;Miyamoto, Tadaaki;Tsujii, Hirohiko
    • Proceedings of the Korean Society of Medical Physics Conference
    • /
    • 2002.09a
    • /
    • pp.90-93
    • /
    • 2002
  • In particle radiotherapy, a shape of the beam to conform the irradiation field is statically defined by the compensator, collimator and potal devices at the outside of the patient body. However the target such as lung or liver cancer moves along with respiration. This increases the irradiated volume of normal tissue. Prior discussions about organ motions along with respiration have been mainly focused on inferior-superior movement that was usually perpendicular to beam axis. On the other hand, the change of the target depth along the beam axis is very important especially in particle radiotherapy, because the range end of beam (Bragg peak) is so sharp as to be matched to distal edge of the target. In treatment planning, the range of the particle beam inside the body is calculated using a calibration curve relating CT number and water equivalent path length (WEL) to correct the inhomogeneities of tissues. The variation in CT number along the beam path would cause the uncertainties of range calculation at treatment planning for particle radiotherapy. To estimate the uncertainties of the range calculation associated with patient breathing, we proposed the method using sequential CT images with respiration waveform, and analyzed organ motions and WELs at patients that had lung or liver cancer. The variation of the depth along the beam path was presented in WEL rather than geometrical length. In analyzed cases, WELs around the diaphragm were remarkably changed depending on the respiration, and the magnitude of these WEL variations was almost comparable to inferior-superior movement of diaphragm. The variation of WEL around the lung was influenced by heartbeat.

  • PDF